There have been a number of covers developed over the years that are designed for placement about the drive unit portion of an outboard, a sterndrive motor system, or the like. The drive unit is hereby defined as the portion of an outboard motor located beneath the motor's powerhead, and the functionally equivalent portion of a stern drive system (a stern drive system has the engine located within the boat and connected to a drive unit that is affixed to and extends outwardly from the boat's transom). The drive unit therefore includes a number of relatively sharp surfaces including stabilizing and anti-cavitation fins, the propeller and the unit's skeg.
Relevant art covers in this field are designed to either isolate the drive unit from salt water or to protect it from the weather. The covers are in the form of flexible bags or rigid containers that fit around a boat's drive unit. Some of the covers are waterproof so that they can be used as a fresh water tank for flushing of the motor. The covers are typically quite bulky and are not easily stowable.
A common fear of boat owners is that people who are swimming in the area of their boat will accidentally come into contact with the boat's drive unit. Accidental contact can also occur when the boat is out of the water and on a trailer or other type of support structure. The sharp edges of the unit, including those of the propeller, make such contact extremely hazardous.
Another worry of boat owners is that the boat's drive unit may be damaged while the boat is docked or in storage. This can occur if an object is accidentally dropped on the unit or when a tool such as a hammer is being used in the area of the unit and accidentally contacts the drive unit. The fragility of the propeller and the complexity of the parts within the drive unit make even a slight blow a cause for concern.